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Indiana University Studies
Phylogenetic History
Epoch | Time estimate, millions of years |
Geologic events | History of Cynips |
Upper Cretaceous | 80-60 | Rise of flowering plants Origin of oak First rise of Rockies and Sierras |
Ancestral Cynipidae |
Eocene | 60-35 | Alaskan-Siberian connection maintained, climate mild, oak in the area | Differentiation of main groups in the family |
Oligocene | 35-20 | Alaskan-Siberian connection maintained, climate mild, oak in the area Great Plains forming |
Cynips and other modern genera in existence Eastern and western subgenera separated |
Miocene | 20-7 | Alaskan-Siberian connection continuous, climate more severe Rockies elevating, deserts forming in the area Finally Alaskan land connections broken |
Subgenus Cynips moves into Eurasia Antron and Besbicus species differentiate on Pacific Coast Acraspis, Atrusca and Philonix specific stocks arise in southern Rockies |
Pliocene | 7-1 | Great Valley of Calif. in part an inland sea Rockies elevated and Great Plains become semi-arid Sierras elevated and Great Basin becomes more arid |
Specific stocks of eastern subgenera move across Great Plains Modern species and varieties differentiated in all groups |
Pleistocene | 1 million to 20,000 years | Grand Canyon begun Extensive glaciation Cold climate south to Ohio River Moist climate in parts of Great Basin and north of Gulf of California |
Northern varieties pushed south to hybridize with southern varieties Some Calif, species migrate back to so. Arizona |